codec_codec2.c File Reference

Translate between signed linear and Codec 2. More...

#include "asterisk.h"
#include "asterisk/codec.h"
#include "asterisk/frame.h"
#include "asterisk/linkedlists.h"
#include "asterisk/logger.h"
#include "asterisk/module.h"
#include "asterisk/rtp_engine.h"
#include "asterisk/translate.h"
#include <codec2/codec2.h>
#include "asterisk/slin.h"
#include "ex_codec2.h"

Include dependency graph for codec_codec2.c:

Go to the source code of this file.

Data Structures
struct	codec2_translator_pvt

Macros
#define	BUFFER_SAMPLES   8000
#define	CODEC2_FRAME_LEN   6 /* consider codec2_bits_per_frame(.) */
#define	CODEC2_SAMPLES   160 /* consider codec2_samples_per_frame(.) */

Functions
static void	__reg_module (void)
static void	__unreg_module (void)
struct ast_module *	AST_MODULE_SELF_SYM (void)
static void	codec2_destroy_stuff (struct ast_trans_pvt *pvt)
static int	codec2_new (struct ast_trans_pvt *pvt)
static int	codec2tolin_framein (struct ast_trans_pvt *pvt, struct ast_frame *f)
	decode and store in outbuf.
static int	lintocodec2_framein (struct ast_trans_pvt *pvt, struct ast_frame *f)
	store samples into working buffer for later decode
static struct ast_frame *	lintocodec2_frameout (struct ast_trans_pvt *pvt)
	encode and produce a frame
static int	load_module (void)
static int	unload_module (void)

Variables
static struct ast_module_info	__mod_info = { .name = AST_MODULE, .flags = AST_MODFLAG_LOAD_ORDER , .description = "Codec 2 Coder/Decoder" , .key = ASTERISK_GPL_KEY , .buildopt_sum = AST_BUILDOPT_SUM, .load = load_module, .unload = unload_module, .load_pri = AST_MODPRI_DEFAULT, .support_level = AST_MODULE_SUPPORT_CORE, }
static const struct ast_module_info *	ast_module_info = &__mod_info
static struct ast_translator	codec2tolin
static struct ast_translator	lintocodec2

Detailed Description

Translate between signed linear and Codec 2.

Author

Alexander Traud pabst.nosp@m.raud.nosp@m.@comp.nosp@m.user.nosp@m.ve.co.nosp@m.m

Note

http://www.rowetel.com/codec2.html

Definition in file codec_codec2.c.

Macro Definition Documentation

BUFFER_SAMPLES

#define BUFFER_SAMPLES   8000

Definition at line 47 of file codec_codec2.c.

CODEC2_FRAME_LEN

#define CODEC2_FRAME_LEN   6 /* consider codec2_bits_per_frame(.) */

Definition at line 49 of file codec_codec2.c.

CODEC2_SAMPLES

#define CODEC2_SAMPLES   160 /* consider codec2_samples_per_frame(.) */

Definition at line 48 of file codec_codec2.c.

Function Documentation

__reg_module()

static void __reg_module ( void  )

static

Definition at line 222 of file codec_codec2.c.

__unreg_module()

static void __unreg_module ( void  )

static

Definition at line 222 of file codec_codec2.c.

AST_MODULE_SELF_SYM()

struct ast_module * AST_MODULE_SELF_SYM

(

void

)

Definition at line 222 of file codec_codec2.c.

codec2_destroy_stuff()

static void codec2_destroy_stuff ( struct ast_trans_pvt *  pvt )

static

Definition at line 141 of file codec_codec2.c.

{
    struct codec2_translator_pvt *tmp = pvt->pvt;
 
    if (tmp->state) {
        codec2_destroy(tmp->state);
    }
}

References ast_trans_pvt::pvt, and codec2_translator_pvt::state.

codec2_new()

static int codec2_new ( struct ast_trans_pvt *  pvt )

static

Definition at line 60 of file codec_codec2.c.

{
    struct codec2_translator_pvt *tmp = pvt->pvt;
 
    tmp->state = codec2_create(CODEC2_MODE_2400);
 
    if (!tmp->state) {
        ast_log(LOG_ERROR, "Error creating Codec 2 conversion\n");
        return -1;
    }
 
    return 0;
}

References ast_log, LOG_ERROR, ast_trans_pvt::pvt, and codec2_translator_pvt::state.

codec2tolin_framein()

static int codec2tolin_framein ( struct ast_trans_pvt *  pvt, struct ast_frame *  f  )

static

decode and store in outbuf.

Definition at line 75 of file codec_codec2.c.

{
    struct codec2_translator_pvt *tmp = pvt->pvt;
    int x;
 
    for (x = 0; x < f->datalen; x += CODEC2_FRAME_LEN) {
        unsigned char *src = f->data.ptr + x;
        int16_t *dst = pvt->outbuf.i16 + pvt->samples;
 
        codec2_decode(tmp->state, dst, src);
 
        pvt->samples += CODEC2_SAMPLES;
        pvt->datalen += CODEC2_SAMPLES * 2;
    }
 
    return 0;
}

References CODEC2_FRAME_LEN, CODEC2_SAMPLES, ast_frame::data, ast_frame::datalen, ast_trans_pvt::datalen, ast_trans_pvt::i16, ast_trans_pvt::outbuf, ast_frame::ptr, ast_trans_pvt::pvt, ast_trans_pvt::samples, and codec2_translator_pvt::state.

lintocodec2_framein()

static int lintocodec2_framein ( struct ast_trans_pvt *  pvt, struct ast_frame *  f  )

static

store samples into working buffer for later decode

Definition at line 94 of file codec_codec2.c.

{
    struct codec2_translator_pvt *tmp = pvt->pvt;
 
    memcpy(tmp->buf + pvt->samples, f->data.ptr, f->datalen);
    pvt->samples += f->samples;
 
    return 0;
}

References codec2_translator_pvt::buf, ast_frame::data, ast_frame::datalen, ast_frame::ptr, ast_trans_pvt::pvt, ast_frame::samples, and ast_trans_pvt::samples.

lintocodec2_frameout()

static struct ast_frame * lintocodec2_frameout ( struct ast_trans_pvt *  pvt )

static

encode and produce a frame

Definition at line 105 of file codec_codec2.c.

{
    struct codec2_translator_pvt *tmp = pvt->pvt;
    struct ast_frame *result = NULL;
    struct ast_frame *last = NULL;
    int samples = 0; /* output samples */
 
    while (pvt->samples >= CODEC2_SAMPLES) {
        struct ast_frame *current;
 
        /* Encode a frame of data */
        codec2_encode(tmp->state, pvt->outbuf.uc, tmp->buf + samples);
 
        samples += CODEC2_SAMPLES;
        pvt->samples -= CODEC2_SAMPLES;
 
        current = ast_trans_frameout(pvt, CODEC2_FRAME_LEN, CODEC2_SAMPLES);
 
        if (!current) {
            continue;
        } else if (last) {
            AST_LIST_NEXT(last, frame_list) = current;
        } else {
            result = current;
        }
        last = current;
    }
 
    /* Move the data at the end of the buffer to the front */
    if (samples) {
        memmove(tmp->buf, tmp->buf + samples, pvt->samples * 2);
    }
 
    return result;
}

References AST_LIST_NEXT, ast_trans_frameout(), codec2_translator_pvt::buf, CODEC2_FRAME_LEN, CODEC2_SAMPLES, current, last, NULL, ast_trans_pvt::outbuf, ast_trans_pvt::pvt, result, ast_frame::samples, ast_trans_pvt::samples, codec2_translator_pvt::state, and ast_trans_pvt::uc.

load_module()

static int load_module ( void  )

static

Definition at line 206 of file codec_codec2.c.

{
    int res = 0;
 
    res |= ast_register_translator(&codec2tolin);
    res |= ast_register_translator(&lintocodec2);
    res |= ast_rtp_engine_load_format(ast_format_codec2);
 
    if (res) {
        unload_module();
        return AST_MODULE_LOAD_DECLINE;
    }
 
    return AST_MODULE_LOAD_SUCCESS;
}

References ast_format_codec2, AST_MODULE_LOAD_DECLINE, AST_MODULE_LOAD_SUCCESS, ast_register_translator, ast_rtp_engine_load_format(), codec2tolin, lintocodec2, and unload_module().

unload_module()

static int unload_module ( void  )

static

Definition at line 195 of file codec_codec2.c.

{
    int res = 0;
 
    res |= ast_rtp_engine_unload_format(ast_format_codec2);
    res |= ast_unregister_translator(&lintocodec2);
    res |= ast_unregister_translator(&codec2tolin);
 
    return res;
}

References ast_format_codec2, ast_rtp_engine_unload_format(), ast_unregister_translator(), codec2tolin, and lintocodec2.

Referenced by load_module().

Variable Documentation

__mod_info

struct ast_module_info __mod_info = { .name = AST_MODULE, .flags = AST_MODFLAG_LOAD_ORDER , .description = "Codec 2 Coder/Decoder" , .key = ASTERISK_GPL_KEY , .buildopt_sum = AST_BUILDOPT_SUM, .load = load_module, .unload = unload_module, .load_pri = AST_MODPRI_DEFAULT, .support_level = AST_MODULE_SUPPORT_CORE, }

static

Definition at line 222 of file codec_codec2.c.

ast_module_info

const struct ast_module_info* ast_module_info = &__mod_info

static

Definition at line 222 of file codec_codec2.c.

codec2tolin

struct ast_translator codec2tolin

static

Definition at line 150 of file codec_codec2.c.

                                           {
    .name = "codec2tolin",
    .src_codec = {
        .name = "codec2",
        .type = AST_MEDIA_TYPE_AUDIO,
        .sample_rate = 8000,
    },
    .dst_codec = {
        .name = "slin",
        .type = AST_MEDIA_TYPE_AUDIO,
        .sample_rate = 8000,
    },
    .format = "slin",
    .newpvt = codec2_new,
    .framein = codec2tolin_framein,
    .destroy = codec2_destroy_stuff,
    .sample = codec2_sample,
    .desc_size = sizeof(struct codec2_translator_pvt),
    .buffer_samples = BUFFER_SAMPLES,
    .buf_size = BUFFER_SAMPLES * 2,
};

Referenced by load_module(), and unload_module().

lintocodec2

struct ast_translator lintocodec2

static

Definition at line 172 of file codec_codec2.c.

                                           {
    .name = "lintocodec2",
    .src_codec = {
        .name = "slin",
        .type = AST_MEDIA_TYPE_AUDIO,
        .sample_rate = 8000,
    },
    .dst_codec = {
        .name = "codec2",
        .type = AST_MEDIA_TYPE_AUDIO,
        .sample_rate = 8000,
    },
    .format = "codec2",
    .newpvt = codec2_new,
    .framein = lintocodec2_framein,
    .frameout = lintocodec2_frameout,
    .destroy = codec2_destroy_stuff,
    .sample = slin8_sample,
    .desc_size = sizeof(struct codec2_translator_pvt),
    .buffer_samples = BUFFER_SAMPLES,
    .buf_size = (BUFFER_SAMPLES * CODEC2_FRAME_LEN + CODEC2_SAMPLES - 1) / CODEC2_SAMPLES,
};

Referenced by load_module(), and unload_module().